Hi Bruce and others, Back in the day, I used to use a "trick" for generating feff files for non-crystalline, molecular substances (or small nanoclusters). I'd use a space group of P 1 with a = b = c = 100, and alpha = beta = gamma = 90...then I could enter coordinates in hundredths of an Angstrom. But I tried the trick recently, and the Atoms inside Artemis complains that I should be using a cubic space group and doesn't run. I don't know my space groups very well, but is there actually a cubic group that doesn't have any symmetry within the unit cell? It seems to me that a real material (not just my trick) could have an "accidentally" cubic unit cell without being a cubic space group. Can someone who knows crystallography better than I do confirm that? If so, then atoms could issue a warning, but should not prevent a feff.inp file from being generated. Incidentally, of course I know there's a fairly trivial alternative to my trick...I could just create the feff.inp file without using atoms (Artemis even conveniently provides a template). But I think it's marginally easier for some of those new to the software to use the P 1 method, because then they don't have to think about potential lists and such. --Scott Calvin Sarah Lawrence College